I tested the 734pm’s brightness, contrast ratio, and color coverage using our standard test gear: a Klein K-10A colorimeter, a Murideo 8K SixG signal generator, and Portrait Displays’ Calman Ultimate for Business calibration software.
HP rates the 734pm’s luminance at 400 nits (candelas per meter squared), and in our testing, it easily cleared that, at 492 nits. The panel has a VESA DisplayHDR 400 rating. I measured its HDR luminance at 514 nits and peak HDR brightness at 562 nits.
The 734pm turned in a healthy 1,974:1 contrast ratio. HP rates its color coverage at 100% of the sRGB space and 98% of Display P3; it effectively matched both of these with 98.7% coverage of both sRGB (see the chromaticity chart below) and DCI-P3. Display P3 is Apple’s implementation of DCI-P3 and is very similar to that color space.
(Credit: Portrait Displays)
I also tested the 734pm’s Delta E (dE), a measure of color accuracy, namely the difference between the hue of a displayed color and the color input the monitor received. The lower the dE, the more accurate the color. An average dE of below 2 indicates color accurate enough that a casual observer may be unable to distinguish any variation between the color on the screen and the intended (source) color. I measured the dE at 1.08. That’s an excellent figure, particularly because the 734pm is pitched as a productivity monitor rather than a dedicated creator-centric monitor, and the company makes no specific claim about the display’s dE.
In the ad-hoc, experiential part of our testing, I viewed selected video clips as well as our photo suite on the 734pm. Images were bright, with realistic-looking colors and good retention of detail in both light and dark areas.